<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>作用域</title>
</head>

<body>
  <script>
    // ============================== 作用域 ============================== 

    // 块级作用域
    // if (true) {
    //   let y = 200
    // }


    
    
    // 全局作用域


  </script>
</body>

</html>